Normal variation for the personality trait of schizotypy may have origins that overlap the etiological factors that produce the psychiatric disease schizophrenia. Although schizophrenia has been widely researched in many disciplines for decades, the causes of this complex disease still remain elusive. For diseases where factors influencing ordinary variation in the population are the same as those that are etiologically relevant to the diagnosis of disease, a large unselected sample may contribute beneficially to research on many traits instead of just one. Furthermore, the use of quantitative measures in such a sample provides the advantage of tapping into variation in the low and middle ranges, not just the diagnostically significant high ends of trait distributions.